You've described a normal action that happens ever time you fire a shot until the last round in the magazine. If it's bad for the extractor, the design is very flawed. If you're worried about bullet set-back, don't chamber rounds over and over again. Shoot the chambered round next range day and freshen up the bullets when you get back home.

If you're talking about dropping one in the tube and letting the slide go, it's not necessary although some guns are better suited to handled this than others.